Telkom ruined my Credit Score & I was denied Vehicle Finance

I cancelled my ADSL line and phone line on the 5th of April 2017 and on the 21st of April again but Telkom kept invoicing me until the 14th of July 2018 before handing my account over to debt collectors whom I sent all the proof of cancellation to on 23 October 2018. I was denied vehicle financing today because of this and looks like I'll miss out of a bargain car which I also need urgently. This is surely an infringement on my rights and the CPA, Telkom needs to fix their error and repair my credit history hopefully IMMEDIATELY!!! Complaints will be lodged with the National Consumer Commission, Ombudsman, ICASA, social media and any other place that I can find and I'll be looking into legal representation too. You people are messing with people lives!